The present invention is related to the field of information retrieval, and in particular to the field of providing document change information to a user.
The ever-increasing universe of electronic information, for example as found on the World Wide Web (herein after referred to as the Web), competes for the effectively fixed and limited attention of people. Both consumers and producers of information want to understand what kinds of information are available, how desirable it is, and how its content and use change through time.
Making sense of very large collections of linked documents and foraging for information in such environments is difficult without specialized aids. Collections of linked documents are often connected together using hypertext links. The basic structure of linked hypertext is designed to promote the process of browsing from one document to another along hypertext links, which is unfortunately very slow and inefficient when hypertext collections become very large and heterogeneous. Two sorts of aids have evolved in such situations. The first are structures or tools that abstract and cluster information in some form of classification system. Examples of such would be library card catalogs and the Yahoo! Web site (URL http://www.yahoo.com). The second are systems that attempt to predict the information relevant to a user""s needs and to order the presentation of information accordingly. Examples would include search engines such as Lycos (URL: http://www.lycos.com), which take a user""s specifications of an information need, in the form of words and phrases, and return ranked lists of documents that are predicted to be relevant to the user""s need.
Another class of tools is recommender systems. Recommender systems provide a list of recommended subsequent web pages worth viewing based on some predetermined filtering criteria. One such recommender tool is the xe2x80x9cRecommendxe2x80x9d feature provided on the Alexa Internet Web site (URL: http://www.alexa.com). The xe2x80x9cRecommendxe2x80x9d feature provides a list of related Web pages that a user may want to retrieve and view based on the Web page that they are currently viewing.
Another recommender system is termed xe2x80x9cthe Knowledge Pumpxe2x80x9d and is described by Glance, N., Arregui, D. and Dardenne, M. xe2x80x9cKnowledge Pump: Supporting the Flow and Use of Knowledge.xe2x80x9d In Information Technology for Knowledge Management. Eds. U. Borghoff and R. Pareschi, New York: Springer-Verlag, pp. 35-45, 1998. The xe2x80x9cKnowledge Pumpxe2x80x9d was designed for use within organizations and has a key focus on the sharing of information in the form of documents.
Prospective applications of recommender systems are as information sharing applications for organizations. Here, the quality of the recommendation service is key. If the recommender system fails to recognize stale references and changes in recommended documents, the users"" experience of the information sharing environment will suffer significantly as a result. In other words, a main failing of recommender systems currently is that they provide static recommendations of potentially dynamic objects.
Changes to documents are also of interest to users. Such changes can take many forms: substantive content change, cosmetic/syntactic changes, and disappearance of the document. In addition, administrators of data stores containing document references face the additional problem that the same document can be referenced by multiple references.
Some repositories and databases are equipped with tools, using triggers, that help users deal with these problems by notifying users when referenced items of interest change in some way or are removed. On the WWW, there are now also several services available to help users monitor Web pages based on their Uniform Resource Locator (URL) address, such as: netmind, Smart Bookmarks, Grassroots, xe2x80x9cWebTrackerxe2x80x94a Web Service for tracking documentsxe2x80x9d by Fishkin, K. and Bier, E.
netmind: http://www.netmind.com,
Smart Bookmarks: http://www.firstfloor.com/SmartBookmarks2.0/QuickStart.html,
Grassroots: http://www-pcd.stanford.edu/Grassroots,
xe2x80x9cWebTrackerxe2x80x94a Web Service for tracking documents,xe2x80x9d by Fishkin, K. and Bier, E. available at http://www.parc.xerox.com/istl/members/fishkin/doc/webtracker.html.
These services notify users when URLs they have registered with the service have changed in some way. In addition, they may also be able to federate the change monitoring systems of other kinds of networked repositories. However, evaluating the nature of the change and its importance for the user is a difficult task to automate and is thus the weakness of such change monitoring systems. The agent notifications while perhaps including a great deal of data concerning the change, may be potentially irrelevant to the user, and in the long run, the high noise vs. signal ratio may cause the user more annoyance than aid. The most accurate way to evaluate the nature and importance the change remains the user him/herself, at least for the foreseeable future.
In addition, within a given workgroup, work community, or organization, it is likely that the existence of substantive changes in a document will be relevant to a number of people, not just one. In this case, the work of evaluating the nature of the change is likely to be done not once but many times, as there is currently no good way to share this work.
A document recommendation system incorporating a document change monitoring agent is disclosed. As described above with respect to the prior art, there are a number of problems that are experienced by users of networked repositories. The present invention addresses several that stem from the fact that access to these repositories is typically done via document references that point to documents. The problems that arise are: (1) the document reference itself may not remain stable (may become stale); (2) the content of document referenced may change; and (3) multiple references may exist for the same item. Solutions that exist today, such as document change monitoring agents on the World Wide Web and change trigger agents within repositories and databases, are entirely automated processes, and as such, do not resolve these problems satisfactorily. In addition, they are oriented to single users as opposed to groups of users.
The present invention addresses these issues by coupling a document change monitoring agent, which automatically detects changes in referenced documents, with a recommender system, which helps users share and evaluate information in a collaborative way. An important advantage of the present invention is that it brings human judgement into the relevance evaluation of the detected changes and allows the results to be shared with other people likely to be interested, in such a way that redundant work is decreased.
The present invention shows how this limitation can be overcome by, first of all, coupling a document change monitoring agent with the recommender system and, secondly, implementing a collaborative process for evaluating the nature and importance of these changes. It has been determined through research and experience with existing recommender systems, that such functionality is key to improving the usability of a recommender system intended for sharing information in the form of documents.
A system implementation of the present invention may include the following elements: a document recommendation element for providing document recommendations to a user based on a user profile, said document recommendation element further comprising one or more action elements for responding to a change in a recommended document, each of said one or more action elements performing a different action based on the nature of said change; document representation storage, for storing representations of said recommended documents; a document registration element coupled to said document recommendation element, said document registration element for enabling a user to identify recommended documents for which they would like to be notified of changes; a document change monitoring element coupled to said document registration element, said document change monitoring element for detecting a change to said document and reporting said change to said document recommendation element; and a user notification element coupled to said document recommendation element, said user notification element for notifying users of said change.